Combustion engine



June 11, 1929. w. RIEHM COMBUSTION ENGINE Filed April 11, 1925 Patented June 11, 1929.

UNITED STATES I 1,716,978 PATENT OFFICE.

WILHELM RIEHM, OF AUGSBURG, GERMANY, ASSIGNOR TO THE FIRM: MASCHINEN- FABRIK AUGSBURG-NUERNBERG, AKTIENGESELLSCHAFT, OF AUGSBUBG,

MANY, A CORPORATION OF GERMANY.

GER-

COMBUSTION ENGINE.

Application filed April 11, 1925, Serial No. 22,329, and in Germany August 20, 1924. I

This invention relates to combustion engines and more particularly to' a device for the solid injection of the fuel (without air) for crude oil motors. In the ordinary devices of this kind, when using gas-oils, and to an especially large extent when using heavy oils, there are formed deposits of carbonized oil, oil coke and the like, which assume the form of tubes depositing in front of the openings of the fuel nozzle. These deposits impair the action of the fuel nozzle to a very large extent because they will prevent a proper distribution of the fuel in the combustion space, by deflecting the jet of fuel in its direction and by finally causing a clogging up of the nozzle.

This invention is based upon the observation that a deposit of carbonized oil does not take place, if the nozzle outlets are exposed to the action of an air or gas-stream. According to this invention the nozzle for the fuel is arranged in such a manner, that it will be systematically exposed to a stream of air or gas. Experiments have proven that in such case the nozzles will remain in perfectly clean condition, so that no troubles will arise and a proper operation of.

to a flow of air which is present within the cylinder, for instance in such a way that it willbe exposed to the scavenging or charging stream or to the motion of the air, which is generated for the purpose of intimately mixing the fuel with the combustion air.- Or a stream of air, for instance the stream of the sucked-in air, is so conducted that it will scavenge the nozzle outlets or orifices of the ghannels serving for the injection of the uel.

An especially advantageous effect is obtained, if the air or gas stream is conducted into a chamber surrounding the nozzle, said chamber forming together with the nozzle in the plane of the nozzle outlets or immediately above the same a narrow ring-shaped gap, through which the air or gas stream wi 1 enter the cylinder. This stream is thereby carried under high pressure and with a proper velocity past the nozzle outlets and will thus take away all deposits forming at the nozzle, so that the nozzle will remain always clean on its outside.

The stream of air or gas may be either periodically introduced, that is to say in case of four-stroke engines at every suction stroke by sucking in fresh air, or in case of two-stroke engines during the scavenging period by introducing scavenging air or intermittently introduced by injecting from time to time highly compressed air (starting air) during the suction stroke or during the scavenging period. Alsoin the former case special :pressure air may be used for this purpose.

The invention is particularly illustrated in the accompanying drawing in which Fig. 1 is a vertical sectional view through a portion-of a cylinder illustrating one form of the invention;

Fig. 2 is a horizontal sectional view through a cylinder illustrating a modifica-' tion Fig. 3 is a fragmentary sectional viewcharging stream. In the arrangement shown in Fig. 2 a circular motion of the combustion air is brought about b a deflector fitted to the valve disc which eflects the air in the direction of the arrows e as shown. The nozzle a for the fuel, which in this case also projects into the interior limiting surface f of the c linder or the cylinder cover is so arrange that it will be exposed to the motion of the air roduced for the urpose of mixing the com ustion air with t e fuel, as indicated by the arrows 6.

Fig. 3 shows an arrangement, whereby a screen or deflector h is rovided in front of the suction valve 9, said screen serving to deflect the path of the sucked in air and forcing the same to take its way over the nozzle a for the fuel.

-According to Fig. 4 the nozzle a is surrounded by a chamber 2', which is formed .by a properly bentmetal sheet y fastened at the coverc of the cylinder. Thissheet is provided at its center with a .passage for the nozzle, said passage having such a width, that it will form about in the plane of the orifices of the injection channels-or immediately above the same together with the nozzle a narrow ring-shaped channel k. The chamber i is connected through a bore Z and the conduit m either with the outer air in the case of four-stroke engines or in the arse of two-stroke engines with the container for the scavenging air or with anoth or container for the pressure air or the gas. In the supply conduit there is inserted a valve, which is so controlled, that it will cause air to pass either periodically into the chamber i, such as in case of four-stroke engines at every suction stroke or in case of two-stroke engines during the'scavenging period, or from time to time. In the latter. case, in order to. obtain a sufficient effect, highly compressed air, for instance starting air must be used. The air discharges through the narrow ring-shaped space K: into the cylinder, thereby flowing past the outer side of the nozzle, thus carrying away all deposits forming at the nozzle outlet and permanently keeping all these channels in open condition.

I claim;

1. In an internal combustion engine of the character described, the combination of a cylinder, aufuel-injeotion nozzle for said cylinder, and means for-directing a concentrated fluid stream overthe outlet of said nozzle at times intermediate the periods of fuel injection from said nozzle, said means comprising an enclosing member defining a chamber surrounding the outlet end of the nozzle, said enclosing member having an opening through which said nozzle projects and providing with said nozzle a ringshaped gap adjacent the nozzle outlet, and means for passing the fluid stream through said chamber and gap past the nozzle into the cylinder of the engine to prevent the building up of carbon deposits thereon.

2. An internal combustion engine according to claim 1, in which the fluid stream passage is provided with a valve and controlling means for said valve, whereby said valve is adapted to periodically supply fluid to the chamber surrounding the nozzle.

3. An internal combustion engine according to claim 1, in which the fluid stream passage provided with a valve and controlling means for-said valve. wherebysaid valve is adapted to periodically supply fluid to the chamber surrounding the nozzle, and means to connect the fluid passage to a source of air supply to furnish combustion air to said chamber and cylinder.

4. In a four-cycle internal combustion en gine of the character described, the combination of a cylinder having a cylinder head and providing a combustion space, a fuel injection nozzle protruding into said combustion space and having a fuel port adapted to inject fuel therein substantially at the beginning of the combustion stroke, an enclosing member defining a chamber surrounding the protruding end of said nozzle, said enclosing member having an opening adjacent the fuel port of the nozzle, and means connecting said chamber with the atmosphere whereby a concentrated stream of cooling suction air is directed at high velocity over the protruding end of the nozzle on the suction stroke in order to scavenge said nozzle.

In testimony whereof I have afiixed my signature.

DR. WILHELM RIEHM. 

